Need help programming Regency 4720 - lost code 0

["JOHN- Adelphia" <jdb5@xxxxxxxxxxxx>]

Hello group, I need help.

The previous owner of the home I'm in now changed the default code 0 (5432)
and does not remember the new code.
I can not get into the programming mode and I was wondering if there is a
way to reset the main panel back to the factory default, or is there a way
to "hot" boot into the programming menu?
Or, could I read the code from the eprom using an eprom programmer?
There is what looks like a phone jack on the eprom board. Is this a
programming connection ?
Thanks in advance.

Feel free to e-mail me direct.

jdb5@xxxxxxxxxxxx

John